1. Field of the Invention
The present invention relates to a pen, particularly to a pen with an integrated light source.
2. Description of Related Art
Stationery articles usually are made without integrated light sources. A pen with integrated light source is not only usable for writing, but also for illuminating, performing decorative functions, extending the range of application and enhancing fun of use.
China patent no. 02200769.5 “Pen with light source operated by pressing with soft coating” discloses a pen with an integrated light source, which is operated by thumb-pressing, and a soft coating. The pen has a pin in an eccentric position, an electric circuit and wires. A switch having two terminals controls switching on and off of light. Since the switch and a pen refill are mounted on a common axis, pressing down thereon will cause a ballpoint of the pen to project outward and simultaneously the light source to be switched on. The coating has protective as well as decorative functions. However, there are still structural parts that are required for improvement, like connecting wires, a conductive ring, a casing, a thread, the eccentric pin, a spring, end pins, and another spring. Terminals of a battery have too complicated structures, therefore are too expensive to manufacture and are prone to defects, so that the lifetime of the pen is limited. Furthermore, a case with a metal section is used, in which a lighting element is placed, so that luminosity is reduced.